Slicing disc mower knives

ABSTRACT

A blade for a mower disc body is provided. The blade defines a central axis of rotation. The blade includes a blade body. The blade body is of a first hardness. The blade body has opposed top and bottom surfaces. An outer surface extends around the blade body vertically between the top and bottom surfaces. The blade body comprises first and second apertures or retainer structures in spaced apart relation. A cutting edge extends along an outer surface of the blade.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims the benefit of U.S. Provisional PatentApplication No. 61/991,938, filed May 12, 2014, and U.S. ProvisionalPatent Application No. 62/036,490, filed Aug. 12, 2014, the entireteachings and disclosure of which are incorporated herein by referencethereto.

FIELD OF THE INVENTION

This invention generally relates to mower disc blades (also referred toas knives).

BACKGROUND OF THE INVENTION

Disc mowing machines are utilized to cut a crop while moving through astand of the crop. Examples of such machines are shown for example inU.S. Patent Application Publication No. 2013/0111863. The disc mowingmachines may be either self-propelled or pulled, for example, by atractor.

As disclosed in the '863 publication, current disc mowing machines cutagricultural material using a severing blade that is rectangular inshape with a mounting hole toward one end of the blade. The severingblade is rotatably mounted to a plurality of rotating mower discs. Theportion of the blade away from the mounting portion has a beveled edgeand this portion of the blade impacts and cuts the crop as the discrotates.

There are problems associated with current disc mower machines. Theyrequire a large amount of power to rotate their discs and drive therectangular blades through the crops. The cutting of the crop itself isnot a large percentage of the total power required, but any reduction inpower used is beneficial. Ideally, if the crop can be cut moreefficiently, the amount of fuel used can be reduced.

Additionally, the use of the rectangular blades in operation isproblematic because in operation, they frequently contact small stonesand rocks in the field. At impact the stones are hurled into the air attremendous velocities. Though there are guards and shields in place theyare not always effective at preventing the projectiles from impactingthe machine operator or bystanders.

Furthermore, the rectangular blades of current designs become dullalmost immediately upon use and impact with the crop. The blades wearout beyond usefulness in a fairly short time span depending on fieldconditions. Such wear leads to increased expenses and increased time formaintenance to repair and or replace the worn blades.

The invention provides a mower disc blade to address one or more of theforegoing problems with known mower disc blades. These and otheradvantages of the invention, as well as additional inventive features,will be apparent from the description of the invention provided herein.

BRIEF SUMMARY OF THE INVENTION

In one aspect, the invention provides a blade for a mower disc body thatdefines a central axis of rotation. The blade includes a blade body of afirst hardness. The blade body has opposed top and bottom surfaces andincludes an outer surface that extends around the blade body verticallybetween the top and bottom surfaces. The blade body includes first andsecond apertures or retainer structures in spaced apart relation. Acutting edge extends along an outer surface of the blade.

In another aspect, the invention provides a blade for a mower disc body.The blade comprises a blade body of a first hardness. The blade body hasopposed top and bottom surfaces and comprises an outer surface extendingaround the blade body vertically between the top and bottom surfaces.The blade further comprises a first and a second blade body retainer. Acutting edge extends along the outer surface of the blade. The topsurface comprises a plurality of hardened beads spaced apart and of asecond hardness greater than the first hardness. The hardened beads arearranged adjacent to the cutting edge and extend toward the outersurface.

In yet another aspect, the invention provides at least one blade for amower disc body. The mower disc body is adapted to rotate about acentral axis. The mower disc body includes an outer periphery. The atleast one blade includes a blade body. The at least one blade isconfigured such that when it is mounted to the disc mower body the bladebody extends radially outward from the outer periphery an X radialdistance. The at least one blade has a cutting edge that extends along alength of a Y distance from a leading end to a trailing end. The Ydistance is more than 1.5 times as great as the X radial distance.

In still another aspect, the invention provides a mower disc assembly. Amower disc body is adapted to rotate about a central axis of the mowerdisc body. The mower disc body includes an outer periphery. Two bladesare mounted to the disc mower body in diagonally opposed space relation.Each of the blades comprises a hinge retainer that allows articulatingmovement of the blade and a slide retainer. The slide retainer isdisposed at a location trailing the first hinge. Each of the blades hasmovement limited by the slide retainer between a first stop and a secondstop.

In still yet another aspect, the invention provides a mowing machine forslicing crops. The mowing machine includes a blade for a mower disc bodythat defines a central axis of rotation. The blade includes a blade bodyof a first hardness. The blade body has opposed top and bottom surfacesand includes an outer surface that extends around the blade bodyvertically between the top and bottom surfaces. The blade body includesfirst and second apertures or retainer structures in spaced apartrelation. A cutting edge extends along an outer surface of the blade.

In an embodiment the cutting edge extends from a leading location to atrailing location relative to the central axis and predeterminedrotational movement for the blade. The leading location and the trailinglocation are separated by an angular distance of at least 120 degrees.In a more preferred embodiment the angular distance may be at least 30degrees with the leading location and the trailing location separatedbetween 5 and 25 centimeters.

In another embodiment the first and second apertures or retainerstructures comprise a mounting aperture or other hinge retainerstructure that defines a blade body axis of rotation for pivotingmovement. The blade body defines an elongated slot or other slideretainer structure that defines a first stop and second stop adapted tolimit pivoting movement of the blade body.

In an embodiment the Y distance is more than 1.5 times as great as the Xradial distance. The cutting edge extends a distance of between 5 and 25centimeters.

In an embodiment the cutting edge includes a curved portion that definesa tangent that defines an acute angle greater than 45 degrees with aradial extension extending from the central axis of rotation.

In an embodiment the cutting edge may be convex and faces away from themower disc body.

In an embodiment the top surface of the blade body comprises a pluralityof hardened beads spaced apart and of a second hardness greater than thefirst hardness. The hardened beads comprise laser clad materialdeposited along an extension radially inward and perpendicular or within45 degrees of perpendicular to a tangent along the convex cutting edge.

In one embodiment the blade body may include a tapered cutting faceformed into the bottom side and intersecting the cutting edge. Thetapered cutting face may be sandwiched between the top surface and abottom surface of the blade body and extend radially inward from the topsurface to the bottom surface.

In an embodiment the blade includes a mounting structure adapted tomount the blade to the mower disc body.

In an embodiment the cutting edge may be formed along the top surface.

In an embodiment the blade body comprises a sheet steel formed componenthaving a material thickness that is substantially uniform.

In an embodiment the hardened beads are 10 to 30% the thickness of thematerial thickness. The first hardness is between HV 400 and 650 in theVickers scale hardness. The hardened beads comprise at least one of thematerials comprising: tungsten carbide, chrome carbide, iron carbide,ceramic, and other material having a Vickers scale hardness between HV700 to 1400.

In an embodiment the blade body comprises a mounting aperture or otherhinge retainer that defines a blade body axis of rotation for pivotingmovement. The blade body defines an elongated slot or other slideretainer that defines a first stop and second stop that limits thepivoting movement of the blade body.

In an embodiment the cutting edge extends along a trailing path from aleading location to a trailing location relative a predetermined axis ofrotation defined by the mower disc body when the blade is mounted to themower disc body. The blade body may include a leading hardened bead anda plurality trailing hardened beads. The trailing hardened beads may belocated in a series trailing the leading location.

In preferred embodiment the Y distance is more than 2 times as great asthe X radial distance.

In a more preferred embodiment the Y distance is more than 2.5 times asgreat as the X radial distance.

In an embodiment the mower body may rotate in a first direction aboutthe central axis of rotation and the blade body may simultaneously beable to rotate about a first hinge axis of rotation in a second andopposite direction of the first direction.

In an embodiment the mower disc body may include a mounting location fora drive unit. The mounting location may define the center axis ofrotation of the mower disc body. The two blade mounting portions are inopposed space relation. Each blade mounting portion may include a firstand second blade mounting location.

In an embodiment the first and second blade mounting locations of themower disc body may be apertures. The hinge retainer of the mower discblade may be an aperture. The slide retainer of the mower disc blade maybe a slotted aperture. Each of the blades may be mounted to the mowerdisc body with fasteners. One the fastener may be inserted through thefirst aperture of the blade mounting location and the hinge retaineraperture. The other of the fasteners may be inserted through the secondblade mounting location aperture and the slotted aperture.

In an embodiment the mowing machine may include a drive unit. A rotarycutter bar may be operably coupled to the drive unit such that the driveunit drives the rotary cutter bar. At least one mower disc assembly isoperably connected to the rotary cutting bar. The at least one mowerdisc assembly is configured to rotate about a central axis of the mowerdisc assembly.

In still another aspect, the invention provides a method for slicingcrops. The method comprises providing a machine to move through thecrop. The machine comprises at least one mower disc assembly configuredto rotate about a central axis of a mower disc body of the mower discassembly.

In an embodiment, the method may include providing at least two bladesfor mounting to a mower disc body. Each blade may include a blade bodyof a first hardness. The blade body has opposed top and bottom surfacesand comprises an outer surface extending around the blade bodyvertically between the top and bottom surfaces. The blade body comprisesfirst and second apertures or retainer structures in spaced apartrelation and a cutting edge extending along an outer surface of theblade.

In an embodiment, the method may include mounting the at least twoblades to the mower disc body in opposed space relation.

In certain embodiments, the method step for providing the at least twoblades further includes the step of depositing a plurality of hardenedbeads along the top surface of each blade. The hardened beads may bespaced apart and of a second hardness greater than the first hardness.Each blade when mounted to the mower disc body may extend radiallyoutward from a mower body outer periphery an X radial distance. Thecutting edge of each blade extends along a length of a Y distance from aleading end of each blade to a trailing end of each blade. The Ydistance is more than 1.5 times as great as the X radial distance.

In yet another embodiment, the cutting edge may include a leading edgeportion, a center edge portion and a trailing edge portion. The centeredge portion may include graduated cutting teeth.

Each graduated cutting tooth may include a tip face, a relief face and abeveled cutting face arranged to create a step in the cutting edge andthereby make the cutting edge discontinuous along the outer surface. Therelief face may extend transverse and inward away from an outermostperiphery of the cutting edge to create the step. The tip face may belocated at the outermost periphery of the cutting edge. The beveledcutting face may extend transversely between the tip face and the reliefface. Each relief face may extend from either the leading edge portionor one tip face of an upstream graduated cutting tooth.

The graduating cutting teeth may be located in the center edge portion,and the beveled cutting edges get shorter and the relief faces getlonger the farther the graduated cutting teeth are from the leadingportion. The graduated cutting teeth are sharpened to have a segmentedcutting surface.

Other aspects, objectives and advantages of the invention will becomemore apparent from the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of thespecification illustrate several aspects of the present invention and,together with the description, serve to explain the principles of theinvention. In the drawings:

FIG. 1 is an illustration of a tractor pulling a mowing machine;

FIG. 2 is a partly schematic isometric illustration of a disc mowercutter bar including a plurality of discs holding a plurality of mowerblades;

FIG. 3 is a schematic view of a mowing machine;

FIG. 4 is an isometric view of a mower disc assembly;

FIG. 5 is a bottom view of a the blade employed in the mower discassembly of FIG. 4;

FIG. 6 is a side view of the blade of FIG. 5;

FIG. 7 is a top view of the blade of FIG. 5;

FIG. 8 is a top view of the mower disc assembly of FIG. 4;

FIG. 9 is a side elevation view of the mower disc assembly of FIG. 4;

FIG. 10 is a bottom view of a blade employed in the mower disc assemblyof FIG. 4

FIG. 11 is a side view of the blade of FIG. 10;

FIG. 12 is a top view of the blade of FIG. 10;

FIG. 13 is a perspective view of the graduated cutting teeth of FIG. 10;and

FIG. 14 is an exploded partial perspective view of the cutting teeth ofFIG. 13.

While the invention will be described in connection with certainpreferred embodiments, there is no intent to limit it to thoseembodiments. On the contrary, the intent is to cover all alternatives,modifications and equivalents as included within the spirit and scope ofthe invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a tractor 10 pulling a mowing machine 12 through astand of crop 13. The mowing machine 12 may either be self-propelled oras shown here pulled and powered by the tractor 10.

FIG. 2 illustrates a mower disc cutter bar 14 that forms a part of themowing machine 12 shown in FIG. 1. The mower disc cutter bar 14 supportsa plurality of mower disc assemblies 16, which in turn support aplurality of mower disc blades 18 (also known as cutter blades and/orknives).

FIG. 3 illustrates a schematic view of a mowing machine 12. The mowingmachine 12 includes a drive unit 20 for driving a rotary cutter bar 14.The rotary cutter bar 14 includes a plurality of mower disc assemblies16 that each contain a plurality of slicing disc mower blades 18 (seeFIG. 2). While the mowing machine 12 is illustrated as including aplurality of mower disc assemblies 16, it is contemplated that as few asone mower disc assembly 16 could be employed in certain applications.

FIG. 4 illustrates an isometric view of a mower disc assembly 16including slicing disc mower blades 18.

The mower disc assembly 16 includes a mower disc body 22. The mower discbody 22 defines a mounting location 19 which attaches to the rotarycutter bar 14 (see FIGS. 2-3) that is in turn driven by the drive unit20. The drive unit 20 causes the mower disc assembly 16 to rotate abouta mower disc body 22 that defines a central axis of rotation 24. Themower disc body 22 may include two blade mounting locations 21. Eachblade mounting location 21 includes a first blade mounting location 23and a second blade mounting location 25. In the embodiment shown in FIG.4 the first and second blade mounting locations 23, 25 are apertures orboss structures through which fasteners 78 are inserted to mount blade18. While two blade mounting locations 21 are illustrated it can bereadily appreciated that only a single blade mounting location may beprovided on the mower disc body 22 or more than two blade mountinglocations 21 may be provide so long as the blade/blades 18 when mountedare balance during the rotation of the mower disc body 22.

As illustrated, the two blade mounting locations 21 are positionedtoward a bottom of the mower disc body 22 so as to balance the blades 18such that during rotation, the blades 18 will extend outwards beyond amower disc body 22 outer periphery 26 under centrifugal force. Eachblade 18 pivots about a blade body 66 axis of rotation 74. The pivotingmotion is limited by a blade body retainer 58 that will be more fullydescribed below. Accordingly, it is not the intent to limit the mountinglocation structures to apertures or bosses with bolts. Any suitableretainer structure to mount the blade 18 to the mower body 22 may beutilized provided the blade 18 may pivot outwards to extend beyond themower body 22 outer periphery 26 under a centrifugal force generated bythe mower disc body 22 in rotation.

As the mower disc assembly 16 is brought into contact with a crop 13 orfoliage to be mowed, the cutter blades 18 will slicingly impact the cropor foliage and thereby slice an upper portion of the crop or foliagefrom its root system. This slicing of the crop will be more fullyexplained below.

Turning now to FIGS. 5, 6 and 7, respectively, a bottom view, side viewand top view of a blade 18 for a mower disc body 22 are shown. The blade18 may be stamped formed from sheet steel to include a blade body 66 ofa hardness between HV 400 and 650 on Vickers scale. The blade body 66has opposed top 62 and bottom 64 surfaces. An outer surface 60 extendsaround the blade body 66 vertically between the top 62 and bottom 64surfaces. The blade body 66 includes a first 56 and second 58 aperturein spaced apart relation. A cutting edge 28 extends along an outermostperiphery 29 of outer surface 60 of the blade 18. The outermostperiphery 29 of outer surface 60 of the blade 18 may extend a distance Lof typically between 5 and 50 centimeters and more preferably between 5and 25 centimeters.

The first 56 aperture is a retainer structure that defines a blade body66 axis of rotation 74 for pivoting movement. The second retainerstructure 58 may be an elongated slot. The elongated slot 58 defines afirst stop 68 and a second stop 70. The elongated slot 58 is adapted tolimit the pivoting movement of the blade body 66 by way of its stops 68and 70.

The top surface 62 of the blade 18 further includes a plurality ofhardened beads 54 spaced apart and of a second hardness greater than thefirst hardness. The hardened beads 54 may comprise laser clad materialdeposited along an extension 72 extending radially inward towards themower disc body 22 and perpendicular or within 45 degrees ofperpendicular to a tangent 48 along the convex cutting edge 28.

The blade body 66 further includes a tapered cutting face 60 formed intothe bottom surface and intersecting the cutting edge 28. The taperedcutting face 60 is sandwiched between the top surface 62 and the bottomsurface 64 of the blade body 66 and extends radially inward from the topsurface 62 to the bottom surface 64. The cutting edge 28 is formed alongthe top surface 62. The blade body 66 may be comprised of a sheet steelformed component of a material thickness 80 (see FIG. 8) that issubstantially uniform. Typically, the blade material thickness 80 isbetween 3 mm and 6 mm. Thereby, the blade 18 dimensions make itparticularly adapted for use as a mower blade. It may be readilyappreciated that it is not the intent to limit construction of the bladebody 66 only to sheet steel. Comparable materials such as cast steel andstainless steel may be utilized to form the blade body 66.

The hardened beads 54 have a thickness 82 and are 10 to 30 percent ofthe material thickness 80. The steel material hardness of the blade body66 is between HV 400 and 650 in the Vickers Hardness Scale. The hardenedbeads 54 are harder in comparison to the steel blade material and cancomprise at least one of the materials comprising tungsten carbide,chrome carbide, iron carbide, ceramic and other material having aVickers Hardness Scale hardness between HV 700 to 1400. The hardenedbeads may be comprised of laser clad material deposited along aplurality of extensions 72 with each extension 72 spaced apart from theother extensions 72 and each extending transversely away from cuttingedge 28 and radially inwards towards curved edge 32 of blade body 66.The benefit of this is to provide for a self-sharpening blade, that isas the softer blade body material wears away during use, the harderbeads remain as the outermost periphery 29 of the blade 18 therebyproviding for a serrated self-sharpened cutting edge 28.

Turning now to FIGS. 8 and 9, a top view of a mower disc assembly 16 andan elevated side view of the mower disc 16 assembly are illustrated.

A mower disc body 22 is adapted to rotate about a central axis 24. Themower disc body 22 includes an outer periphery 26. At least one blade 18is mounted to the mower disc body 22 and extends radially outward fromthe outer periphery 26 of the mower disc body an X radial distance. Theat least one blade 18 has a cutting edge 28 that extends along a lengthof a Y distance from a leading end 36 to a trailing end 38 of thecutting edge 28. The Y distance in a preferred embodiment the Y distancemay be more than 1.5 times as great as the X radial distance. In a morepreferred embodiment the Y distance may be two times as great as the Xradial distance. In an even more preferred embodiment the Y distance maybe 2.5 times as great as the X radial distance.

The functional benefit of the relationship between the X and Y distanceis to provide a cutting edge 28 length beyond the mower disc body outerperiphery 26 that facilitates the slicing action of the convex blade 18as it moves through a crop 13.

In an embodiment the X distance will be between 5 and 15 centimeters.The Y distance will typically be between 5 and 50 centimeters and morepreferably between 5 and 25 centimeters.

As illustrated, rotation about the central axis 24 of the mower discbody 22 is in a counterclockwise first direction 34. It can be readilyappreciated in yet other embodiments the mower disc assembly 16 may verywell be reoriented to rotate in a clockwise direction. Referencethroughout the description is with respect to the mower disc assembly 16adapted for counterclockwise rotation in first direction 34. However,the claims appended hereto are generic to both rotational directions.

The cutting edge 28 extends along a trailing path from a leading end orlocation 36 to a trailing end or location 38 relative to the centralaxis 24 in predetermined rotational movement defined by the mower discbody 22 when the blade 18 is mounted to the mower disc body 22. Theleading location 36 and the trailing location 38 are separated in apreferred embodiment by an angular distance 44 of at least 120 degrees.In a more preferred embodiment the angular distance 44 is at least 30degrees with the leading location and the trailing location separatedbetween 5 and 25 centimeters.

In an embodiment the functional benefit of this may be to provide acutting edge 28 length beyond the mower disc body outer periphery 26that facilitates the slicing action of the convex blade 18 as it movesthrough a crop 13. The angular separation between the leading edge andthe trailing end allow the crop to be sliced instead of impact cut as isthe case with rectangular blades. The angular separation allows the crop18 to slide along and remain in contact with the cutting edge 28 over alonger time and distance relative to a traditional rectangular bladeimpacting the crop along a limited surface of its blade. The slicingprovided thereby increases blade 18 life because slicing produces lessblade wear than an impact cut from a traditional rectangular blade,further such a blade 18 is more efficient in terms of harvesting thecrop 13 and also demands less power to operate.

The cutting edge 28 includes a curved portion 46 that defines a tangent48 that defines an acute angle 50 that is greater than 45 degrees with aradial extension 52 extending from the central axis. In that manner, theconvex cutting edge 28 has an advantageous length that provides for thegreatest amount of time and distance for the crop 13 to be sliced duringoperation.

The blade body 66 is connected to the mower disc body 22 at a hinge 56that allows for articulating movement of the at least one blade 18. Theblade body 66 is also connected to the mower disc body 22 at a slideretainer 58 at a location trailing the first hinge 56. The at least oneblade 18 has an articulating movement limited by the slide retainer 58between first stop 68 and second stop 70. Under centrifugal forcegenerated by the mower disc boy 22 in rotation, the blade 18 is able topivot about axis 74 until stopped by second stop 70 of the second hinge58. Thus, the mower disc body 22 may rotate in a first direction 34about the central axis of rotation 24 while the blade body 66 issimultaneously able to rotate about the blade body 66 axis of rotation74 in a second and opposite direction of the first direction 34. Theability of the blade 18 to move in a direction opposite that of themower body 22 together with beveled edge 60 provide the advantage ofallowing the blade 18 to give way by rotating away from an obstructionand thereby prevent damage to the blade 18 if the instruction turned itout to be an immovable object. Further, this ability prevents suchundesirable objects such as stones form being hurled into the air attremendous velocities. Instead the blade 18 is able to pivot away fromthe object as the face 60 works to direct a downward force on the objectfurther decreasing any projectile velocity.

When cutting crop with a knife blade, a slicing action rather than animpact/shearing action is more efficient. The way the slicing action inthis embodiment is achieved is by facing the crop being cut with acutting edge that has an oblique angle in relation to the rotatingmotion of the mower disc assembly into the crop being cut. Even morespecifically this slicing action in this embodiment is achieved byfacing the crop 13 being cut with a blade 18 that has the large convexcutting edge 28 over a radially inward tapered cutting face 60 where thetaper extends radially inward from the top surface 62 to the bottomsurface 64.

As the blade 18 is rotating, the stalks of the crop 13 come into contactwith the convex cutting edge 28. The blade 18 begins to impact the stalk13 and stalks 13 start sliding along the edge of the direction of leastresistance. This happens in a matter of a very few milliseconds sincethe blade 18 is traveling at approximately 80 meters per second, but theeffects of the sliding action are realized in the amount of energy usedto severe the stalks is reduced.

The blade body 66 includes a leading hardened bead 76 and a plurality oftrailing hardened beads 54. The trailing hardened beads 54 are locatedin series trailing the leading location 36. The laser clad hard metalbeads 54 running tangent to the cutting edge 28 allow the cutting edge28 to self-sharpen. That is, the blade body 66 of the first hardnesswears at a much faster rate than the hardened metal beads 54 of thesecond hardness. Thus, as the softer material of the first hardnesserodes radially inward the hardened beads 54 are left in place andcreate the desired self-sharpening effect of a serrated cutting edge 28.

Typically, a rectangular blade wears primarily at the corner of theouter leading edge of the blade. Further a conventional rectangularmower blade does not slice the crop as does the convex cutting edge 28,rather it impacts the crop to cut it. In this way, the typicalrectangular blade quickly becomes dull and the cutting efficienciescontinue to get worse until the blade is no longer useful. Thus, anadvantage of the present embodiment is that the convex cutting edge 28may provide four times the amount of cutting edge of a typicalrectangular blade's cutting edge. Further, with the convex cutting edge28 the cutting of the crop is distributed evenly along the entire lengthof the cutting edge 28 to provide an even wear pattern thus outlastingthe conventional rectangular blade by approximately four times. Also,because the cutting of the crop 13 is evenly distributed along at thecurved cutting edge 28, the cutting efficiencies will tend to remain thesame from the start of the blade until it is completely worn out.

In an embodiment two blades 18 are mounted to the disc mower body 22 indiagonally opposed space relation. It can be readily appreciated theaforementioned mounting permits a balanced rotation of the mower discbody 22 about central axis 24. Accordingly, more or less blades 18 inyet other embodiments are envisioned. For example, an embodiment mayhave four blades 18 mounted to the mower disc body 22 provided they areopposed space relation and balanced when the mower disc body 22 is inrotation about central axis 24.

Turning now to FIGS. 10, 11 and 12, respectively, a bottom view, sideview and top view of a blade 118 for a mower disc body 22 (FIG. 4) areshown. The blade 118 is similar in most respects to blade 18 (FIG. 5)previously discussed but differs in that graduated cutting teeth 184 areformed into the blade body 166 at the time the blade body 166 is formedwhich may be by stamping for a non-limiting example.

Thus, as with blade 18, blade 118 with its graduating cutting teeth 184may be formed from sheet steel to include the blade body 166 of ahardness between HV 400 and 650 on Vickers scale. The blade body 166 hasopposed top 162 and bottom 164 surfaces. An outer surface 160 extendsaround the blade body 166 vertically between the top 162 and bottom 164surfaces. The blade body 166 includes a first 156 and second 158aperture in spaced apart relation. A cutting edge 128 and extends alongan outermost periphery 129 of outer surface 160 of the blade 118. Thecutting edge 128 of outer surface 160 of the blade 118 may extend adistance L of typically between 5 and 50 centimeters and more preferablybetween 5 and 25 centimeters.

The blade body 166 may be comprised of a sheet steel formed component ofa material thickness 180 that is substantially uniform. Typically, theblade material thickness 180 is between 3 mm and 6 mm. Thereby, theblade 118 dimensions make it particularly adapted for use as a mowerblade. It may be readily appreciated that it is not the intent to limitconstruction of the blade body 166 only to sheet steel. Comparablematerials such as cast steel and stainless steel may be utilized to formthe blade body 166.

The blade body 166 includes a first 156 aperture that is a retainerstructure that defines a blade body 166 axis of rotation 174 forpivoting movement. The second retainer structure 158 may be an elongatedslot. The elongated slot 158 defines a first stop 168 and a second stop170. The elongated slot 158 is adapted to limit the pivoting movement ofthe blade body 166 by way of its stops 168 and 170.

The top surface 162 of the blade 118 further includes a plurality ofhardened beads 154 spaced apart and of a second hardness greater thanthe first hardness. The hardened beads 154 may comprise laser cladmaterial deposited along an extension 172 extending radially inwardtowards the mower disc body 22 and perpendicular or within 45 degrees ofperpendicular to a tangent 148 along the cutting edge 128. The hardenedbead 154 has a maximum circumferential width 155 that extends along thecutting edge 128 of the top surface 162 of the blade body 166.

Unlike blade 18, here, the cutting edge 128 of the blade 118 includesthe graduated cutting teeth 184. Thus the cutting edge 128 containscutting segments 177 that break up the continuous cutting edge 128 ofthe previous embodiments discussed with respect to blade 18. Each tooth184 is formed between each of the spaced hardened beads 154. Thus, thecutting edge 128 is comprised of a trailing edge portion 190, a centeredge portion 194, and a leading edge portion 196. (FIG. 12). The leadingedge portion may be free from any of the graduated cutting teeth 184 andextends along the outer surface 160 of the blade 118 a greater distancethan any individual tooth of the graduated cutting teeth 184.

The trailing edge portion 190 and the leading edge portion 196 of thecutting edge 128 are similar in that each include a tapered cutting face161 formed into the bottom surface 164 and intersecting the cutting edge128. The tapered cutting face 161 is sandwiched between the top surface162 and the bottom surface 164 of the blade body 166. The taperedcutting face 161 extends radially inward to the bottom surface 164 andforms in an embodiment an angle 163 between 30 and 60 degrees with thetop surface 162 of the blade body 166. In a preferred embodiment theangle is between 30 and 45 degrees, and in a more preferred embodimentthe angle is between 30 and 32 degrees. This same angle 163 is presentin all the blade 18 embodiments heretofore described with respect to topsurface 62 and cutting face 60, as cutting face 60 tapers radiallyinward to meet bottom surface 64 along the cutting edge 128.

The center edge portion 194 extends along the cutting edge 128 betweenthe leading edge portion 196 and trailing edge portion 194 and comprisesbetween 50 percent and 90 percent of the cutting edge 128 of blade 118.

The hardened beads 154 and the graduated cutting teeth 184 extend alongthe cutting edge 128 in the center edge portion 194 of the blade body166. The center edge portion 194 in an embodiment may have 3 to 20cutting teeth. In a preferred embodiment the center edge portion mayhave between 4 and 15 cutting teeth 184 and an even more preferredembodiment the center edge portion may have between 5 and 10 cuttingteeth 184.

Turning now to FIGS. 13-14, each cutting tooth 184 of the center edgeportion 194 is comprised of a tip face 186, a relief face 188 and abeveled cutting face 189.

The tip face 186 has a maximum beveled cutting face length 204 along topsurface 162 that approximates a maximum circumferential length 155 ofthe hardened bead 154. The tip face 186 extends inward toward curvededge 132 and in a tapered fashion from the top surface 162 to the bottomsurface 164 to form a tip face taper 212. The tip face taper 212 isintended to approximate the taper 161 of the leading edge portion andtrailing edge portion of cutting edge 128.

The relief face 188 of the tooth 184 extends from approximately a tipface trailing edge 208 to an inward most beveled cutting face edge 210of the beveled cutting face 189 and thereby providing a depth 187. Thus,the relief face 188 extends transversely and inwardly away from theoutermost periphery 129 of the cutting edge 128. Typically the depth 187is between 5 mm and 25 mm. In a preferred embodiment the depth isbetween 5 mm and 10 mm.

Further, the relief face 188 extends from the top surface 162 to thebottom surface 164. The relief face 188 and the beveled cutting face 189meet to form and angle 202 between the two faces 188, 189 at the topsurface 162 of the valve body 166. In an embodiment, the angle 202 maybe between 60 and 120 degrees. In a preferred embodiment, the angle maybe between 80 and 100 degrees. In a more preferred embodiment, the anglemay be between 90 and 91 degrees. The relief face 188 and the beveledcutting edge face 189 are arranged to create a step 176.

The beveled cutting face 189 extends from a tip face trailing edge 206to the inward most beveled cutting face edge 210 and thereby providesfor a beveled cutting face length 191 of the beveled cutting face 189extending along the top surface 162 of the blade body 166. The beveledcutting face length 191 along the top surface 162 is one of the cuttingedge 128 segments 177 previously discussed. The beveled cutting facelength 191 of each of the beveled cutting faces 189 gradually decrease,that is get shorter, with each tooth 184 the farther the graduated teeth184 are from the leading end 136. (FIG. 12) The beveled cutting face 189tapers radially inward from the top surface 162 to the bottom surface164. The taper 210 of the beveled cutting face 189 may be obtained bysharpening on a machine such as a mill for example to provide a flatcutting edge and surface.

The hardened beads 154 have a thickness 182 and are 10 to 30 percent ofthe material thickness 180. The steel material hardness of the bladebody 66 is between HV 400 and 650 in the Vickers Hardness Scale. Thehardened beads 154 are harder in comparison to the steel blade materialand can comprise at least one of the materials comprising tungstencarbide, chrome carbide, iron carbide, ceramic and other material havinga Vickers Hardness Scale hardness between HV 700 to 1400. The hardenedbeads 154 may be comprised of laser clad material deposited along aplurality of extensions 172 with each extension 172 spaced apart fromthe other extensions 172 and each extending transversely away fromcutting edge 128 and radially inwards towards curved edge 132 of bladebody 166. The benefit of this is to provide self-sharpening for blade118. That is, as the softer material of the blade body 166 wears awayduring use, the harder beads 154 remain to cut crop 13 (FIG. 1) andthereby improve the cutting action of the already serrated cutting edge128. By such self-sharpening, the life of blade 118 is increased evenmore than that of the embodiments discussed with blade 18.

In addition to extending blade 118 life, other advantages of the cuttingblade 118 with cutting teeth 184 include cutting crop 13 in nibbles,that is small bites, along the cutting edge 128. It can be readilyappreciated that each tooth 184 provides for a slicing action in cuttingcrop 13 (FIG. 1) along the sharpened beveled cutting face 189 withlength 191 that gets shorter and the relief face 18 that gets longer thefarther the graduated cutting teeth are from the leading end 136. Thesegraduated lengths provides optimal bites, that is cutting of the crop 13in nibbles as crop 13 traverses the segmented central cutting edgeportion 194. Further, advantage is found with this embodiment as justdiscussed with the self-sharpening of the blade 118 that is the resultof the wearing away of the blade body 166 material that is softer thanthat of the hardened beads 154. Thus, the cutting efficiency and bladelife are thereby extended by this particular blade body 118 with thecutting teeth 184 along the center edge portion 194 of the cutting edge128.

All references, including publications, patent applications, and patentscited herein are hereby incorporated by reference to the same extent asif each reference were individually and specifically indicated to beincorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) is to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

1. A blade for a mower disc body that defines a central axis ofrotation, the blade comprising: a blade body of a first hardness, theblade body having opposed top and bottom surfaces and comprising anouter surface extending around the blade body vertically between the topand bottom surfaces; wherein the blade body comprises first and secondapertures or retainer structures in spaced apart relation; and a cuttingedge extending along an outer surface of the blade.
 2. The blade ofclaim 1, wherein the cutting edge extends from a leading location to atrailing location relative to the central axis and predeterminedrotational movement for the blade, the leading location and the trailinglocation separated by an angular distance of at least 120 degrees. 3.The blade of claim 2, wherein the angular distance is at least 30degrees with the leading location and the trailing location separatedbetween 5 and 25 centimeters.
 4. The blade of claim 1, wherein the firstand second apertures or retainer structures comprise a mounting apertureor other hinge retainer structure that defines a blade body axis ofrotation for pivoting movement and wherein the blade body defines anelongated slot or other slide retainer structure that defines a firststop and second stop adapted to limit pivoting movement of the bladebody.
 5. The blade of claim 1, wherein the blade is configured such thatwhen mounted to the mower disc body via the first and second aperturesor retainer structures extends radially outward therefrom an X radialdistance, the blade having a cutting edge that extends along a length ofa Y distance from a leading end to a trailing end, the Y distance beingmore than 1.5 times as great as the X radial distance.
 6. The blade ofclaim 5, wherein the cutting edge extends a distance of between 5 and 25centimeters.
 7. The blade of claim 1, wherein the cutting edge includesa curved portion that defines a tangent that defines an acute anglegreater than 45 degrees with a radial extension extending from thecentral axis of rotation.
 8. The blade of claim 1, wherein the cuttingedge is convex and faces away from the mower disc body.
 9. The blade ofclaim 1, wherein the top surface comprises a plurality of hardened beadsspaced apart and of a second hardness greater than the first hardness;the hardened beads comprise laser clad material deposited along anextension radially inward and perpendicular or within 45 degrees ofperpendicular to a tangent along the convex cutting edge.
 10. The bladeof claim 9, wherein the blade body further includes a tapered cuttingface formed into the bottom side and intersecting the cutting edge; thetapered cutting face sandwiched between the top surface and a bottomsurface of the blade body and extending radially inward from the topsurface to the bottom surface.
 11. A blade for a mower disc body, theblade comprising: a blade body of a first hardness, the blade bodyhaving opposed top and bottom surfaces and comprising an outer surfaceextending around the blade body vertically between the top and bottomsurfaces; a first and a second blade body retainer; a cutting edgeextending along the outer surface of the blade; and wherein the topsurface comprises a plurality of hardened beads spaced apart and of asecond hardness greater than the first hardness, the hardened beadsarranged adjacent to the cutting edge and extending toward the outersurface.
 12. The blade of claim 11, wherein the blade includes amounting structure adapted to mount the blade to the mower disc body,and wherein the cutting edge is convex and faces away from the mountingstructure.
 13. The blade of claim 11, wherein the cutting edge is formedalong the top surface.
 14. The blade of claim 12, wherein the blade bodycomprises a sheet steel formed component having a material thicknessthat is substantially uniform.
 15. The blade of claim 12, wherein thehardened beads are 10 to 30% the thickness of the material thickness;and wherein the first hardness is between HV 400 and 650 in the Vickersscale hardness.
 16. The blade of claim 11, wherein the hardened beadscomprises at least one of the materials comprising: tungsten carbide,chrome carbide, iron carbide, ceramic, and other material having aVickers scale hardness between HV 700 to
 1400. 17. The blade of claim11, wherein the blade body further includes a tapered cutting faceformed into the bottom surface and intersecting the cutting edge; thetapered cutting face sandwiched between the top surface and a bottomsurface of the blade body and extending radially inward from the topsurface to the bottom surface.
 18. The blade of claim 17, wherein thehardened beads comprise laser clad material deposited along an extensionextending radially inward and perpendicular or within 45 degrees ofperpendicular to a tangent along the convex cutting edge.
 19. The bladeof claim 11, wherein the blade body comprises a mounting aperture orother hinge retainer that defines a blade body axis of rotation forpivoting movement; and wherein the blade body defines an elongated slotor other slide retainer that defines a first stop and second stoplimiting pivoting movement of the blade body.
 20. The blade of claim 19,wherein the cutting edge extends along a trailing path from a leadinglocation to a trailing location relative a predetermined axis ofrotation defined by the mower disc body when the blade is mounted to themower disc body, the leading location and the trailing location beingseparated by an angular distance of at least 60 degrees, the blade bodyincluding a leading hardened bead and a plurality trailing hardenedbeads, the trailing hardened beads located in a series trailing theleading location.
 21. A blade for a mower disc body adapted to rotateabout a central axis, wherein the mower disc body includes an outerperiphery; wherein the blade comprises a blade body; and the blade bodyis configured such that when mounted to the mower body the blade bodyextends radially outward from the outer periphery an X radial distance,the blade having a cutting edge that extends along a length of a Ydistance from a leading end to a trailing end, the Y distance being morethan 1.5 times as great as the X radial distance.
 22. The blade of claim21, wherein the cutting edge extends from a leading location to atrailing location relative to the central axis and predeterminedrotational movement, the leading location and the trailing locationseparated by an angular distance of at least 120 degrees.
 23. The bladeof claim 22, wherein the angular distance is at least 30 degrees withthe leading location and the trailing location separated between 5 and25 centimeters.
 24. The blade of claim 21, wherein the Y distance ismore than 2 times as great as the X radial distance.
 25. The blade ofclaim 21, wherein the Y distance is more than 2.5 times as great as theX radial distance.
 26. The blade of claim 21, wherein the cutting edgeincludes a curved portion that defines a tangent that defines an acuteangle greater than 45 degrees with a radial extension extending from thecentral axis.
 27. The blade of claim 21, wherein the at least one bladefurther comprises a blade body of a first hardness; and wherein the topsurface comprises a plurality of hardened beads spaced apart and of asecond hardness greater than the first hardness.
 28. A mower discassembly including the blade of claim 21, wherein the blade body isconnected to the mower disc body at a hinge allowing articulatingmovement of the at least one blade, the blade body is also connected tothe mower disc body at a slide retainer at a location trailing the firsthinge, the at least one blade having the articulating movement limitedby the slide retainer between first and second stops.
 29. The mower discassembly of claim 28, wherein the mower body rotates in a firstdirection about the central axis of rotation and the blade body issimultaneously able to rotate about a first blade body hinge axis ofrotation in a second and opposite direction of the first direction. 30.A mower disc assembly, comprising at least two of the blades of claim 1,the mower disc assembly comprising: a mower disc body adapted to rotateabout a central axis of the mower disc body; the mower disc bodyincluding an outer periphery; and wherein the at least two blades aremounted to the disc mower body in opposed space relation; each of theblades comprising a hinge retainer allowing articulating movement of theblade and a slide retainer disposed at a location trailing the firsthinge, the blade having articulating movement limited by the slideretainer between a first stop and a second stop.
 31. The mower discassembly of claim 30, wherein the mower disc body includes: a mountinglocation for a drive unit; the mounting location defining the centeraxis of rotation of the mower disc body; and two blade mounting portionsin opposed space relation, each blade mounting portion including a firstand second blade mounting location.
 32. The mower disc assembly of claim30, wherein each blade comprises: a blade body of a first hardness, theblade body having opposed top and bottom surfaces and comprising anouter surface extending around the blade body vertically between the topand bottom surfaces; a convex cutting edge extending along the outersurface of the blade; and wherein the top surface comprises a pluralityof hardened beads spaced apart and of a second hardness greater than thefirst hardness.
 33. The mower disc assembly of claim 32, wherein themower disc body rotates in a first direction about the central axis ofrotation and each blade may simultaneously rotate about a first hingeaxis of rotation in a second and opposite direction than the firstdirection.
 34. The mower disc assembly of claim 33, wherein the firstand second blade mounting locations of the mower disc body areapertures; the hinge retainer of the mower disc blade is an aperture;and wherein the slide retainer of the mower disc blade is a slottedaperture.
 35. The mower disc assembly of claim 34, wherein each of theblades are mounted to the mower disc body with fasteners; one of thefasteners inserted through the first aperture of the blade mountinglocation and the hinge retainer aperture; the other of the fastenersinserted through the second blade mounting location aperture and theslotted aperture.
 36. A mowing machine for slicing crops including atleast one of the blades of claim 1, the mowing machine comprising: adrive unit; a rotary cutter bar operably coupled to the drive unit suchthat the drive unit drives the rotary cutter bar; and at least one mowerdisc assembly operably connected to the rotary cutting bar, the at leastone mower disc assembly configured to rotate about a central axis of themower disc assembly. 37-39. (canceled)
 40. The blade of claim 9, whereinthe cutting edge comprises a leading edge portion, a center edge portionand a trailing edge portion; the center edge portion including graduatedcutting teeth.
 41. The blade of claim 40, wherein each graduated cuttingtooth includes a tip face, a relief face and a beveled cutting facearranged to create a step in the cutting edge and thereby make thecutting edge discontinuous along the outer surface, the relief faceextending transverse and inward away from an outermost periphery of thecutting edge to create the step, the tip face being at the outermostperiphery of the cutting edge, the beveled cutting face extendingtransversely between the tip face and the relief face, each relief faceextending from either the lead edge portion or one tip face of anupstream graduated cutting tooth.
 42. The blade of claim 41, wherein thegraduating cutting teeth are located in the center edge portion, and thebeveled cutting edges get shorter and the relief faces get longer thefarther the graduated cutting teeth are from the leading portion. 43.The blade of claim 41, wherein the graduated cutting teeth are sharpenedto have a segmented cutting surface.
 44. The blade of claim 11, whereinthe cutting edge comprises a leading edge portion, a center edge portionand a trailing edge portion; the center edge portion including graduatedcutting teeth.
 45. The blade of claim 44, wherein each graduated cuttingtooth includes a tip face, a relief face and a beveled cutting facearranged to create a step in the cutting edge and thereby make thecutting edge discontinuous along the outer surface, the relief faceextending transverse and inward away from an outermost periphery of thecutting edge to create the step, the tip face being at the outermostperiphery of the cutting edge, the beveled cutting face extendingtransversely between the tip face and the relief face, each relief faceextending from either the lead edge portion or one tip face of anupstream graduated cutting tooth.
 46. The blade of claim 44, wherein thegraduating cutting teeth are located in the center edge portion, and thebeveled cutting edges get shorter and the relief faces get longer thefarther the graduated cutting teeth are from the leading portion. 47.The blade of claim 44, wherein the graduated cutting teeth are sharpenedto have a segmented cutting surface.
 48. The blade of claim 27, whereinthe cutting edge comprises a leading edge portion, a center edge portionand a trailing edge portion; the center edge portion including graduatedcutting teeth.
 49. The blade of claim 48, wherein each graduated cuttingtooth includes a tip face, a relief face and a beveled cutting facearranged to create a step in the cutting edge and thereby make thecutting edge discontinuous along the outer surface, the relief faceextending transverse and inward away from an outermost periphery of thecutting edge to create the step, the tip face being at the outermostperiphery of the cutting edge, the beveled cutting face extendingtransversely between the tip face and the relief face, each relief faceextending from either the lead edge portion or one tip face of anupstream graduated cutting tooth.
 50. The blade of claim 48, wherein thegraduating cutting teeth are located in the center edge portion, and thebeveled cutting edges get shorter and the relief faces get longer thefarther the graduated cutting teeth are from the leading edge portion.51. The blade of claim 48, wherein the graduated cutting teeth aresharpened to have a segmented cutting surface.
 52. The method of claim51, wherein each blade wherein the cutting edge comprises a leading edgeportion, a center edge portion and a trailing edge portion; the centeredge portion including graduated cutting teeth.
 53. The blade of claim52, wherein each graduated cutting tooth includes a tip face, a reliefface and a beveled cutting face arranged to create a step in the cuttingedge and thereby make the cutting edge discontinuous along the outersurface, the relief face extending transverse and inward away from anoutermost periphery of the cutting edge to create the step, the tip facebeing at the outermost periphery of the cutting edge, the beveledcutting face extending transversely between the tip face and the reliefface, each relief face extending from either the lead edge portion orone tip face of an upstream graduated cutting tooth.
 54. The blade ofclaim 52, wherein the graduating cutting teeth are located in the centeredge portion, and the beveled cutting edges get shorter and the relieffaces get longer the farther the graduated cutting teeth are from theleading portion.
 55. The blade of claim 52, wherein the graduatedcutting teeth are sharpened to have a segmented cutting surface.